摘要
水中溶存甲烷含量是水环境与资源调查的重要指标之一。目前实验室测量该项指标时,通常是利用甲烷在水中的理论亨利常数。而甲烷在不同类型水中的亨利常数并不相同,若追求更高精度的测量,需要先行测定甲烷的亨利常数。本文以实验原液水中溶解甲烷为主要研究对象,提出测定原液水中甲烷亨利常数的加标/顶空平衡法。研制了气液平衡配液装置,研究了5 L封闭体系的气液平衡时间。系统推导了气液等体积和非等体积情况下,根据气相甲烷浓度和不同平衡体系的MaddV求解甲烷亨利常数的关系式。并利用该方法实测出1个大气压25℃时实验原液水的甲烷亨利常数为64226792 Pa·L/mol,最后通过MCH4addV与MaddV比较法对实验结果进行了验证。
Static headspace-GC method was used to determine the concentration of methane in water.In the static headspace-GC method,Henry’s law constant of methane in water has been usually thought to be the theoretical value;nevertheless,in fact,Henry’s law constant of methane is not the same in different sorts of“water”.For the purpose of providing the higher determination accuracy,Henry’s law constant of methane in the water should be determined first before using static headspace-GC method.A method for determination of Henry’s law constant of methane in water is presented in this paper.A device for gas-liquid equilibrium was developed.The time of gas-liquid equilibrium was studied.Formulas about Henry’s law constant were derived systematically with the concentration of methane of only gas phase equilibrium and MaddV between two phase equilibriums.The experimental result is that Henry’s law constant of methane in the test water is 64226792 Pa·L/mol under atmospheric condition of 25℃.At last the result was proved to be correct through the comparative study of MCH4addV and MaddV.
作者
刘广虎
温明明
邓丽婷
崔浩楠
贾永永
程思海
曹珺
李超
LIU Guang-hu;WEN Ming-ming;DENG Li-ting;CUI Hao-nan;JIA Yong-yong;CHENG Si-hai;CAO Jun;LI Chao(Key Laboratory of Marine Mineral Resources,Ministry of Natural Resources,Guangzhou,Guangdong 510760;Institute of Disaster Prevention,Sanhe,Hebei 065201;Key Laboratory of Earthquake Dynamics in Hebei Province,Sanhe,Hebei 065201;Guangzhou Marine Geological Survey,Guangzhou,Guangdong 510760;Hebei GEO University,Shijiazhuang,Hebei 050031;China University of Geosciences(Beijing),Beijing 100083)
出处
《地球学报》
CAS
CSCD
北大核心
2021年第4期566-572,共7页
Acta Geoscientica Sinica
基金
自然资源部海底矿产资源重点实验室开放基金(编号:KLMMR-2015-B-05)
国家重点研发计划项目(编号:2016YFC0303902-04)联合资助。
关键词
甲烷
加标
顶空平衡
亨利常数
methane
add reference
static headspace method
Henry’s law constant
